DockerHub rate limiting impacts Workspaces creation for cloning of projects

MR: Pending

Description

We use the upstream git container image hosted on DockerHub to clone the projects during workspace creation. With recently announced DockerHub rate limits which came into effect April 1, 2025, our customers might run into some of them. We should mitigate them by doing one/many of the following

• Use a container image hosted on GitLab Container Registry (simplest)
• Allow customers to bring in their own container image of git for cloning
• Eliminate the need for the git container image altogether

Acceptance criteria

• [Describe what must be achieved to complete this issue.]
• [If applicable, please provide design specifications for this feature/enhancement.]
• [If applicable, please list any technical requirements (performance, security, database, etc.)]

Implementation plan

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[Provide a high-level plan for implementation of this issue, including relevant technical and/or design details.]